The pterygoid is a paired bone forming part of the palate of many vertebrates, behind the palatine bones. In humans it becomes the pterygoid processes of the sphenoid bone. This anatomy article is a stub. Answer : (b)

Joint between humerus and radio-ulna is Hinge Answer : (d)

Answer : (b)

Answer : (a)

The human skull is generally considered to consist of twenty-two bones—eight cranial bones and fourteen facial skeleton bones. In the neurocranium these are the occipital bone, two temporal bones, two parietal bones, the sphenoid, ethmoid and frontal bones Answer : (a)

The pubic symphysis is a secondary cartilaginous joint (a joint made of hyaline cartilage and fibrocartilage) located between the left and right pubic bones near the midline of the body Answer : (b)

The scapula, a triangular, flat bone, lies on the posterolateral aspect of the thorax, overlying the 2nd to 7th ribs. Answer : (b)

The human skull is generally considered to consist of twenty-two bones—eight cranial bones and fourteen facial skeleton bones. In the neurocranium these are the occipital bone, two temporal bones, two parietal bones, the sphenoid, ethmoid and frontal bones. Bones of the head: There are 29 bones in the human head. They consist of 8 cranial bones, 14 facial bones, the hyoid bone, and 6 auditory (ear) bones. Answer : (a)

A sprain is a stretched or torn ligament. Answer : (a)

A hinge joint is a common class of synovial joint that includes the ankle, elbow, and knee joints. Hinge joints are formed between two or more bones where the bones can only move along one axis to flex or extend. Answer : (b)

Muscular dystrophy (MD) is a group of muscle diseases that results in increasing weakening and breakdown of skeletal muscles over time. Statement (a) is correct Myasthenia gravis is a rare neuromuscular disorder that causes weakness in the skeletal muscles. Statement (b) is correct Gout is a type of arthritis that causes inflammation, usually in one joint, that begins suddenly. Gouty arthritis is caused by the deposition of crystals of uric acid in a joint. Statement (c) is wrong Osteoporosis is a condition of fragile bone with an increased susceptibility to fracture. Osteoporosisweakens bone and increases risk of bones breaking. Statement (d)is correct Answer : (d)

The greater trochanter - A powerful protrusion located at the proximal (near) and lateral (outside) part of the shaft of the femur. The greater trochanter is also called the major trochanter, the outer trochanter, and the lateral process of the femur. The lesser trochanter - A pyramidal prominence that projects from the proximal (near) and medial (inside) part of the shaft of the femur. The lesser trochanter is also called the minor trochanter, the inner trochanter, and the medial process of the femur. Answer : (c)

Troponin is distributed at regular intervals on the tropomyosin. Statement (ii) is wrong Answer : (d)

The human skull is generally considered to consist of twenty-two bones—eight cranial bones and fourteen facial skeleton bones. In the neurocranium these are the occipital bone, two temporal bones, two parietal bones, the sphenoid, ethmoid and frontal bones. Answer : (b)

Shank is the part of the lower limb in humans between the knee and the ankle Answer : (d)

Glycogen is a stored form of glucose. It is a large multi-branched polymer of glucose which is accumulated in response to insulin and broken down into glucose in response to glucagon. Lactic is converted to glucose in Liver. Answer : (a)

At rest, troponin molecules hold tropomyosin fibers so that they cover the myosin-binding sites on actine Answer : (d)

The smooth muscle of the alimentary canal (the digestive tract) facilitates the peristaltic waves that move swallowed food and nutrients. Answer : (a)

The occipital condyles are undersurface protuberances of the occipital bone in vertebrates, which function in articulation with the superior facets of the atlas vertebra. Statement (a) wrong. The 11th and 12th pairs—floating ribs.Statement (c) is wrong. The head of the femur (thigh bone) articulates with the acetabulum in the pelvic bone forming the hip joint Statement (d) wrong. The skull bones are connected by fibrous joints called sutures. Statement (b) is true Answer : (b)

The metacarpophalangeal joints (MCP) refer to the joints between the metacarpal bones and the phalanges of the fingers. The interphalangeal joints of the hand are the hinge joints between the phalanges of the fingers that provide flexion towards the palm of the hand. Answer : (c)

The ridge on the humerus where the deltoid muscle is attached. The pectoral and deltoid ridges are important points of muscle attachment. The pectoral ridge extends from the greater tubercle along the medial edge of the bone and the deltoid ridge extends from the greater tubercle along the lateral edge of the bone. Answer : (b)

Answer : (d)

Tail vertebrae or coccygeal vertebraeThe four terminal segments of the vertebral column, usually fused to form the coccyx. Humerus and ulna have simple hinge-joint which is Synovial joint. The skull bones are connected by fibrous joints called sutures. The facet joints, are a set of synovial, plane joints between the articular processes of two adjacent vertebrae. Answer : (b)

Answer : (a)

White muscle fibres are designed for quick movements (like the muscles in hands& for moving eyes). Also they are used for high energy activity for short periods of time. Due to this they need more sarcoplasmic reticulumThe sarcoplasmic reticulum (SR) constitutes the main intracellular calcium store in striated muscle and plays an important role in the regulation of excitation-contraction-coupling (ECC) and of intracellular calcium concentrations during contraction and relaxation. Red Muscles(Example: extensor muscle on back of human body) 1.Red muscles are thin muscle fibres 2. Red in colour due to the presence of large amount of myoglobin 3.Slow and sustained contraction 4.Depend on aerobic metabolism for energy (oxidative phosphorylation) 5.Mitochondria is abundant 6.No accumulation of lactic acid 7. Perform sustained work for a prolonged period without fatigue (slow but steady) 8.Lesssarcoplasmic reticulum White muscles (Example: Muscles of the eye ball) 1.White muscles are thick muscle fibres 2.White in colour due to less amount of myoglobin 3. Fast contraction 4. Depend on anaerobic metabolism for energy (glycolysis) 5. Mitochondria is less 6.lactic acid accumulation by glycolysis 7.Perform fast and strenuous work for a short period (fast but soon fatigue) 8.highsarcoplasmic reticulum Answer : (d)

Many gliding joints are formed in the appendicular skeleton between the carpal bones of the wrist; between the carpals and the metacarpals of the palm; between the tarsal bones of the ankle; and between the tarsals and the metatarsals of the foot. Answer : (d)

Red Muscle Fibres 1. These muscle fibres are dark red which is due to the presence of red haemoprotein called myoglobin. Myoglobin binds and stores oxygen as oxymyogiobin in the red fibres. Oxymyogiobin releases oxygen for utilization during muscle contraction. 2. Mitochondria are more in number. 3. Red muscles have less sarcoplasmic reticulum. 4. They carry out considerable aerobic oxidation without accumulating much lactic acid. Thus red muscle fibres can contract for a longer period without fatigue. 5. These muscle fibres have slow rate of contraction for long periods. Example: Extensor muscles of the human. Answer : (b)

A synovial joint is a connection between two bones consisting of a cartilage lined cavity filled with fluid. There are six types of synovial joints i)Ball and socket joint ii) Pivot joint iii) Hinge joint iv) Pivot joints v) Condyloid joints vi) Saddle joints Cartilaginous joints are connected entirely by cartilage (fibrocartilage or hyaline). Cartilaginous joints allow more movement between bones than a fibrous joint but less than the highly mobile synovial joint. Answer : (a)

The All-or-None law is the principle that the strength by which a nerve or muscle fiber responds to a stimulus is independent of the strength of the stimulus. If that stimulus exceeds the threshold potential, the nerve or muscle fiber will give a complete response; otherwise, there is no response. A whole skeletal muscle is considered an organ of the muscular system. Each organ or muscle consists of skeletal muscle tissue, connective tissue, nerve tissue, and blood or vascular tissue. Answer : (b)

According to All-or-None law Stimulus several times greater than threshold stimulus is provided to muscle fibre. It will Contract with same force Answer : (a)